Thermostat.



G. A. WELD.

THERMOSTAT.

APKPLIoATIoN rILED 00130, 190s.

Patented sept 14, 1909.

U'NIIED STATEPlENT FECE. 1.

GEORGE' A. Wam or IWINCHESTEVR, MASSACHUSETTS.

THERMOSTAT.

Specification of Letters Patent.

Patented Sept'. 14, 1909.

Original application led y:December 22, 1902, Serial No. 136,154. Divided and this appli cation led October To all whom 'it may concern:

. Be it known that I, GEORGE A. VELD, a citizen of the United States, and a resident oi' Winchester in the county of Middlesex f and State of Massachusetts, have invented certain new and useful Im rovements in Thermostats, of which the :tollowing is a specification.

This invention relates to thermostatic controllers 'to be used in connection with a system of heating and Ventilating, or for other purposes, for controlling the flow of an; operating fluid to a motor, which may be 'connected to regulate the heating and the supply of rairfto such a system.

The particular device of this invention has passages for conducting an `operating fluid and valves operated through Avariations in tem erature to control the amount or to shut o entirely the fioW of such fiuid.

The device is illustrated and described in my ending application for heating and venti ating apparatus, filed December' 22, 1902, Serial No. 136,151, of which case this pi'esciit application is a division.

The accom an in drawinvs illustrate the 5.' b. preferred em odiment or my invention, and thcrenn- Figure 1 represents a longitudinal section. Fig. 2 represents a side elevation. F1g. 3

represents a plan viewof this' device. Fig'. 4- is a detail.

The saine reference characters indicate the saine parts in all the figures. l The thermostat comprises essentially a casing l which is formed as a shell or cu open at one end and into which is screwe a head 2, this head completely closing the casing and leaving therein an open space 3. In one side of the head is formed a passage 4 which opens into the interior space 3 and in the other side is a passage 5 opening into a central bore in the head. The central bore has a thrcadedportion into which is screwed a tubular shell or member 6, the upper end of which projects externally of the casing and is closed by a cap 7, while the inner en extends into the open space of the casing through the head. The ends of the shell or '50 member which project through the head are surrounded by Hpacking 8 secured and conipressed by stu ng-box mechanisms 9, 10 of any suitable construction, for preventing leakage of fluid under pressure from the in- 55 terioi to the exterior of the casing. In the Serial'No. 284,957.

side of the shell or member 6 adjacent passage 5 is formed a port 11. The passages 4 5, port 11, interior bore of the shell or member, and the space 3 of thecasing constitute a yconununicating passage or channel through 50. which air,- water or other fluid may 'flow44 from an inlet tube l2 attached in the inletv l to an outlet tube 13 attached in'line with the passage As the device is arranged in the drawings, 12 indicates the'inlet tube and' p5 13 theoutlet, the direction of fiow of thev fiuid being indicated by the arrows, but itis to be understood that the parts and direction" of flow might be reversed.

The lower end of the shell or member 6, 70 `which before stated is open to the interior of the casing, is formed with an annular valve-seat und coperating therewith is a valve .14 which has a lonfr stein 15 projecting y out through' the endv of the casing. This 75 stein may be of steel or other metal Ihaving a definite coefficient of expansion. 'Surrounding the stem 15 isa tube 160i` a different metal having a definite coefficient of expansion which is different from and preferably greater than that of the stem. One end of thertube is fixed with a tight joint in the casing, while the other end is carried out a considerable distance from the casing and connected with the end Aof the stem. .The -35 length and material of which the tube 16 is* ma de are preferably such that the outer end where'the tube is attached to the valve stem l will have a considerable range of movement under moderate variations of temperature and thereby the valve will be moved toWar andaway from its seat.

With the parts constructed and arranged as herein shown and described, a rising temperature will cause a greater expansion of 915 thetube 16 than of the valve ste-m and will therefore carry the valve 14 away from its seat on the end of the stem, whilea falling temperature will produce the reverse effect, contracting tube 16 and seating valve 14 to 100 close the passage. through shell or member 6. The connection between stem 15 and tube 16 consists of a collar 17 on the stem, forming an abutment which coacts with the end of the tube, a spring 18 being provided for 105 holding the collar against the tube. vOne endA of the spring bears against the collar, while the other is held by a head 20 in u. sleeve 19 surrounding the spring and fixed to the vtube 16. 'By this construction experi- 11'0 lit).

,21 is lixed u -contractioi'i of tube which shoes tl -through which the fl sion ot' tube '1G positively moves the valve away from its stat, while there is a yielding pressure to seat the valve. This allows :tor compression ot lthe spring 18 and prevents injury either to the valve or its seat when 1G continues after the valve has l'iecome seated. i

From the foregoing it Will be seen that when the temperature rises beyond a certain predeterniined amount, valve tsl. is opened and a flow ot operating fluid permitted from inlet Yl2 through outlet 13 to the controlling motor Yt'or a .heating or Ventilating system to shut otl`1 or diminish the heat, while when the temperature tails. the llow is shut olf and the motor pinfniitictlmto produce a reverse action ol.5 whatever mechanism .may lie-providcd.

ln order to regulate the degree ot temperature at which vulve 111- will open or close, the tubular shell or member G may be rotated whereby its threaded engagement with the head 2 causes its inner end to beeither advanced farther into or witlfidraivn' itro'ni the casing, whereby its proximity to the valve lat is altered. il graduated plate pon the exterior ot' the easing and therewith cooperates a pointer 22 .iastened upon the shell or member (l. The plate or dial and g'iointcr togcth e r form an indicator ie adjustment ol the valve and imlicatcs in which direction the shell or member should be turned to causo actuation ot the mechanism at a high or low temperature. ik hand-wheel ll is tinted upon the shell or men ber tor rotating it. The ther-- mostat also has lorovisiiins whereby the Huid in the motor may be released when the supply cui' oll by tulnfing; ot valve ll. This consists ot' a port or vent 'flin the shell. or member which opens into an outlet tube 25 uid may escape when permitted. Between the ports .there is 'tormeijl on the interior oi" the shell or meinbf-r a valve fout i/Li'i with which there coiipl crates a valve 2i' that is normally pressed upon tlu, sont by means ot a spring conv lined within the shell or member t) and abutA ling; at its otherenfl against the tap i." A, siem 2l is connected to the valve 2T and l guider; the latter, being l the spring' while the lult b v the .shell or n'iembcr. preventsI linkage from the outlet arouufl the tube t3. interposed between the valves lli and 2T is a stem il within the shellor member (i which is engagi'ed'at opposite ends by thel valves' and" is ot such a length as to prevent both valves being;` closed at once. l have shown the stem 531. as formed ot t wo members adjustably connected by a threaded shanllj. 4whereby the stem vmay be adjusted should l thesame be necessary. VWhen valve 11i isl moved toward its seat, it engages the stem ield in position by er is itself .retained sluiting-box lol passage E to the Ithe vent-outlet is 'the spring or other 3l and brings the latter into engagement with valve 27, forcing said valve from its seat in opposition to the pressure of spring 28. On the other hand, .when valve 14 is retracted by expansion of tube l16, spring 28 causes valve 27 again to seat. Spring 18 is of greater force than sprin 28 so 'that the action described may take p ace. Valve 27 and vent-opening 24 areV provided to serve as a relief for the operating fluid trapped in the motor controlled by the thermostat when the supply thereto is cut oft' by closing of valve 14. Thus, supposing the thermostat were to control admission of compressed air to a cylinder for operating a piston against sprin pressure to actua'te a heating or Ventilating val-ve, the llow ofair, when the valve is opened.; would tion. When, however, valve 14C is closed, the actuation will he stopped and siniultai'ieousl with closing of valve 14, valve 9.17 controlling,r opened, allowing the air 1n the motor cylinder to escape and the latter to be actuated in the opposite 'device pro vided for that purpose.

vThe advantages of my ,improved thermo? stat are a pparent-` It' is particularly obvious that by intel-posing the relief spring between the thermostat member and the main valve stem, an effective provision is made to prevent injury to the parts due to careless handling and manipulation of the valve, or ex posare to sudden and extreme changes ot' temperature. Y In 'other words the use ot such a cushioning bleunder any condition to seat to such an extent as to cause the vulve to press thereagainst with injurious force. rllhis quality gives my iin'proved thermostat a wide range of usefulness and renders it capable ot' use in connection with all classes ot' apparatus in wh ich it is necessary or desirable to employinstruments Vof this characierr l claims* l. A tlie'rmostat comprising ingr an inlet, an outlet and a vent, a tubular shell'or nunnber adhii'istaljily fitted in said fasing and ha vinili,` a passage connecting said inlet and outlet with said vent, a valve het/Ween the inlet and outlet, a stein carryiiiggl said latter valve, a thermostat member operating to vclose said valve by eontraction, a cushion interposed between said thermostat member and said valve stein Ato compensi-ite for abnormal cont t'or said vent, and adjustable means located within said "tubular member and interposed between said valves for valve as the other valve is closed.

thermostat comprising a casing,r having an inlet and an'outlet, a tubular shell or member extending into the casing, and openingl into the interior thereof and into the nieve the piston in one'direc direction byv means renders it impossiproject the valveA a casing hav opening the' reliel llt) raetion oll th'e loriner, a valve outlet, said shell valve for closing upon which said .mostat member arranged .to close said valve opening,

by contraction, a cushion interposed lbetween said thermostat member and said valve stem to compensate for abnormal contraction of the former, a val-ve for closing said vent a spring Within the tube tending to seat said valve, and a stem within the tube interposed between the two .valves for raising t e vent valve from its seat against the 'pressure of the spring when the thermostat controlled valve is closed.

3. A thermostat comprising a casing, aA

head tightly engaged therewith and having passages formed therein, one of which is open .to the interior of the casing, a tubular shell or member threaded through the head into the interior of the casing, being open at its inner end and closed at its outer end, said shell or member having a port opening into one of the passages in said head, and a second port opening externally of the casing, a valve within the tube arranged when seated to close tlie communication between the ports,

` a spring Within the tube space in the casing exterior to said member, l one of said passages constituting an inlet holding said valve normally to its seat, a second valve arranged to close the inner end of said shell or meinber, a thermostat member for operating the latter valve, lber and interposed between said valves for opening one when the other is closed.

et. A thermostat comprisin a casing, ,a thermostatic tube extending rom said casing, a valve stem contained in said tube and extending into the casing, a valve mounted directly on the inner end of said stem, a tubular member extending into the casing opposite to, and in line with said stem, its inner end forming a seat for said valve, the casing having a passage communicating directly with the interior of said tubular meniber and another passage opening into the and the other an outlet for' the controlling fluid, and a relief spring engaged with said thermostatic tube and valve stem arranged to close the valve upon contraction of said tube and to vield upon further contraction ofthe tube after the valve has been seated.

v A thermostat comprising a casing, a tubular member extending thei'cinto and adjustable to vary the amount by which itextends into the casing, its inner end being open and serving as a valve seat, said casing having passages` and a stem in the shell or mem-v communicating respectively` with the interior ofsaid membcr, and with directly on the inner end thermostatic element inline with said tubular member, a' valve mounted on the end'ofv said stem and movable by the movement thereof against and away seat on the end of said member, and a relief cushion between said thermostatic element and valve stem arranged to cause seating of the valve yieldingly upon contraction of the thermostatic element and to permit adjustment of the tubular member While the valve is seated against the end, thereof.

6. A thermostat comprising a casing having an inlet and an outlet, a tubular shell or member extending into the casing, and opening into the interior thereof and into the outlet, said shell having a vent opening, a valve for closing the end of the tube, a stem upon which said valve is mounted, a thermostat member arranged to close said valve by contraction, thermostat member and said valve stein, to compensate for abnormal contraction of the former, a valve forvclosing said vent opening, 'a spring within the tube tending to seat said valve, and an adjustable stem within the tube interposed between the two valves for raising the vent valve from its seat against the pressure of the spring when the thermostat controlled valve is closed.

7. A thermostat comprising a casing, a tliermostatic tube extending from said casing, a valve stein contained in said tube and extending into the casing, a valve mounted of said stem, a tubular member extending into the casing opposite to, and inline with, said stem, its inner end forming a seat for said valve, the thermostat'having a passage communicating directly with the interior of said tubular member and another passage opening into the space in the casing exterior bei', one of said passages inlet and the other an outlet for the con-` trolling luid, and a relief spring engaged with said therinostatic tube and valve stem arranged to close the valve upon contractiony ofl said tubeand to yield upon further'contraction of the tube after the valve has been' seated. v

In testimony whereof have affixed my signature, in presence of two witnesses.

from the valve.

a cushion interposed between saidto said memconstituting an 

